Forums mIRC Help i tried your advice today on DHCP and Proxy

DMZ to the pc using the computer name, the router well internally resolve that to the Ip of the pc.

Did you try while using 2 mircs on the same machine?

Here is a disturbing possability as well, since DMZ is resolving to the machine name rather than an IP, it might be that you can not have static lan/pc ips under the comcast router, it might refuse to forward to anything that is not dhcping its Ip from the router (i have seen this in non linksys models, netburst or netgear i think it was), however since your the only pc behind it the router "should" always issue the same ip to the pc, as it well take the first dhcp ip on offer, meaning you could still forward to it, Is the PC ip Static (set in the actual pc) or dynamic but is returning the same value all the time?

As Riamus2 has said already I suggest you try a alternative router.